Mining-machine chain.



F. L. SESSIONS MINING MACHINE CHAIN.

APPLICATION FILED OCT. 9. l9. RENEWED MAR. 27. l9l7- Patented Oct. 3 .17.

EETS-SH Hil nub/two F; L.' SESSIONS.

MINING MACHINE CHAIN. v 7 APPLICATION FILED OCT. 9. NH. RENEWED MAR. 27.19H.

Patented Oct. 30, 1917.

2 SHEETS-SHEET 2.

FRANK I1. SESSIONS, OF COLUMBUS, OHIO.

MINING-MACHINE CHAIN.

Specification of Letters Patent.

Application filed October 9, 1911, Serial No. 653,5?0. Renewed March 27, 1917. Serial No. 157,848.

walls 8, the bottomfaces 6 parallel to the, v

To all 'wkom may concern Be it known that I, FRANK L. SESSIONS,

I a citizen of the United States, residing at Columbus, in the county of Franklin and State of Ohio, have invented certain new and useful Improvements in Mining-Machine Chains, of which the following is a specification, reference being had therein to the accompanying drawing.

This invention relates to mining machine chains andin particular to improvements in chains provided with detachable bits.

An object of this invention is to provide a mining machine chain in which the bits may be properly and quickly inserted without adjustment A further object is the elimination of troublesome set screws and clamping devices for retaining the bit in the chain.

In the drawings,

Figure 1 is a plan view of a block link adapted to carry three hits.

Fig. 2 is an end elevation of a block link such as is shown in Fig. 1.

Fig. 3 is an end elevation of a block link adapted to carry two bits.

Fig. 4 is an. end elevation of a strap link adapted to carry one bit.

Fig. 5 is a plan view of the strap link shown in Fig. 4;.

Fig. 6 is a plan view of a pick-point bit. I

Fig. 7 is a side elevation of the bit shown inFig. 6.

- Fig. 8 is an end elevation of the bit shown in Fig. 6..

Fig. 9 is a horizontal longitudinal sectional view of the link shown in Fig. 2 with a bit inserted iuthe central socket.

Fig. 10 is a plan View of a section of a mining machine chain showing two sets of seven hits.

Fig. "11 is a side elevation of the chain section shown in Fig. 10.

In thedrawings, the numeral 1 indicates the body portion of a link upon the upper side of which is cast a flat shelf 2 carrying upward extending lugs 3 which, when in combinations of two or more, are connected by webs 4:. Sockets formed in thelugs 3 are indicated in general by the numerals, 5, and

one of the principal features of this invention isthe forming of these sockets approximately parallel to the line of motion of the chain. As shown in the drawings, the

sockets are formed with two parallel side links, and the upper faces 7 inclined downward from the front so as to form rearward tapering sockets. The socket illustrated in the drawings is of the preferred type, although it may be made in anyone of a numberof ways without departing from the spirit of the invention.

The bit illustrated in Figs. 6,7 and 8 is of the preferred form and is made up of a Patented a so, ram.

shank 9 shaped at one end intoa head 10,

the upper portion of. which is formed into a pick-point 11. so raked as to operate or cut on a. line parallel to-the lower. face of the shank. The form illustrated is adapted for use .in the socket as shown in Figs. 2, 3,4

and 9. As previously stated, the socket may be of any one of a number of types, and requires in each case a bit having a shank particularly adapted for that type of socket. Where the socket and shank are formed with the upper and lower faces sloped, the pick-point is shaped to cut on a line parallel to the axis of the shank. The object is in each case to have the pick-point operate parallel to the line along'which the shank moves in being forced into its socket.

7 The lower part of the cutting end of the tool is formed into-a head. 10 for the purposecf providing a surface against which blows may be delivered in driving the bit into its socket.

It is preferable that the bit be cast or forged of steel of a higher grade than that usually employed for this work. When made in this manner the cost of manufacturing is very slightly increased, but since the life of the bit is greater it will be much cheaper, when worn out, to discard and replace by a new bit than to redress the point as is the present practice. In this manner, the expense of operating a mining machine chain is very much reduced.

I have shown in the drawings three types of bit holder's; a block link holding three hits, a block link holding two bits, and strap links carrying bits ofiset at each side of the chain. When used in this combination seven bits are carried upon three links forming a set. The sets of bit carrying links, together with the spacing links between each set comprise the chain.

In Figs. 10 and 111 have shown a section of chain comprising two sets of seven hits separated by .one llllk. In operation it is found that they may be separated by three .or more blank links depending on the nature of the coal to be cut.

In manufacturing the bit, a slot 18 is formed in the end of the shank opposite the pick-point either in casting, or by slotting out before the bit is hardened. This is provided so that the end of the shank may be spread after inserting in a socket to insure the bit from loosening and coming out.

The principal feature of this type of bit and chain is the forming of the pickoint, shank and socket so that the shank in eing forced into the socket follows a line parallel to the line of cut. Because of this structure, it is unnecessary to set the point of each individual bit a proper distance away from the chain as is necessary in the ordinary type of chain. Should the bit loosen and work out of the socket there is no danger of its protruding and bitin into the coal too far, or jamming against t e machine.

It will be seen that it does not matter whether my bit is driven into the socket to the shoulder formed by the angle of the cutter head or not. The cutting edge or point will remain'the same distance from the finished surface against which the chain slides while cutting, regardless of the position longitudinally of the bit as related to the chain. This feature is a distinct advantage in saving time when replacing hits as it does away entirely with set screws or other retaining devices for the bits.

What I claim is:

1. In a mining machine chain, the combination of a series of integral cast links, some of which are provided with sockets each open at both ends and havingrearward converging outer and inner wal is parallel to the center line of the chain, all of the said parallel walls being equidistant from the said center line, and a series of bits s of which one 1 each having a shank with rearward converging faces adapted to engage the said converging walls of one of the sockets, the cutting edges of all of the said bits being equidistant from the planes of the shank faces which engage the said parallel socket walls. 7

2. In a mining machine chain, the combination of a series of integral cast links, some of which are provided with sockets, each open at both ends and having rearward converging outer and inner walls, the several inner walls being parallel to the center line of the chain and equidistant therefrom, and a series of bits each havin a shankgwith rearward converging facesa apted to engage the said converging walls of one of the sockets, the cutting edges of all of the said bits being equidistant from the planes of the inner faces of the corresponding shanks.

3. In a mining machine chain, the combination of a series of links, some of which are provided withsockets each having rearward converging outer and inner walls of which one is parallel to the center line of the chain, all of the said parallel walls being equidistant from the said center line, and a series of bits each having a shank with rearward converging faces adapted to engage the said converging walls .of one of the sockets, the cutting edges of all of the said bits being equidistant from the planes of the shank faces which engage the said parallel socket, walls, and the rear parts of the shanks being longitudinally slotted and spread to hold the bits in lace.

In testimony whereof I a my signature, in presence of two witnesses.

. FRANK L. snss ons. v Witnesses:

KATE Moons, Errm K. MERWINE. 

